Your cats get no meat? They are omnivores and do not eat fruits and veggies as part of their natural diet. Grains are not good for them - I feed only grain free food to mine.
Mischevious, I've been studying cat nutrition since I got my most recent two kitties - the best diet you can feed is RAW, but for me and my schedule, RAW just doesn't work.
Wet diet is now preferred over dry, or at the very least, the wet should make up a higher percentage of their food intake with a quality dry kibble to nibble on during the day. I like Innova Evo (thanks Kara!) and I've got links to nutritional content in different canned brands that I can link here if you'd like.
Read http://www.catinfo.org for more information on cat nutrition.